The 4-(carbomethoxy)-2-phenyl-A2-oxazoline formed from L-serine provides the basis for a useful synthesis of ceramides and cerebrosides. The natural erythro configuration and its threo epimer are formed in equal amounts but are readily separated chromatographically, so that both epimers are available for experiments in which the properties of erythro and threo configurations are to be compared. The method produces the final cerebroside product on ...